This invention relates to rudders, and more particularly concerns rudder means for use with electric trolling motors.
Electric trolling outboard motors are in widespread use, particularly on small boats designed for fishing on island or other relatively calm waters. The low speeds and quiet operation of the trolling motors minimize disturbance of the fish in the waters being fished.
Most electric trolling motors are provided with a smooth, circular shaft connecting the submerged drive motor and propeller assembly with batteries and control means aboard the boat. In contrast, gasoline operated outboard motors are generally provided with an elongated, streamlined housing contoured to function as a rudder. At trolling speeds, an electric motor, when suitably rotated about a vertical axis provides a steering effect ordinarily provided by a rudder. However, at very slow speeds, or when the motor is not running, the boat cannot be steered by positioning movement of the motor. A guard vane or blade, sometimes referred to as a "skag", is generally positioned beneath the electric motor forwardly of the propeller for the purpose of protecting the propeller from impact with hard objects. Such protecting vanes, however, provide little, if any steering effect.
In earlier efforts to impart better steering function to outboard motors, rudder-like panels have been affixed to the motor shaft. U.S. Pat. No. 4,634,388 discloses the attachment of a rudder panel to the shaft of an electric trolling motor at a site above the motor/propeller assembly. Although effective in principle, the stability of the attachment relative to rotative displacement about the shaft is questionable. Furthermore, the space created between the rudder and the motor/propeller assembly impairs streamlining characteristics and serves to catch and accumulate vegetation often encountered at fishing locations.
It is accordingly an object of the present invention to provide a rudder which may be easily and securely attached to an electric trolling motor.
It is another object of this invention to provide a rudder as in the foregoing object which provides a streamlined effect and avoids accumulation of aquatic vegetation.
It is a further object of the invention to provide a rudder of the aforesaid nature which additionally serves to reduce the level of sound emitted from the motor.
It is a still further object of this invention to provide a rudder of the aforesaid nature of rugged, durable design and amenable to low cost manufacture.
These objects and other objects and advantages of the invention will be apparent from the following description.